The primary objective of the program is to further understand HIV infection in infants and children and its effects on disorders of the heart and lung. To this end we will: 1. collect information on the prenatal course and subsequent pulmonary cardiac growth, development and function of Group I: Infants and children with recently diagnosed, perinatally transmitted symptomatic HIV infection; Newborn infants of mothers infected with HIV; Newborn infants of mothers who are seronegative for HIV infection but at high risk of infection for HIV 2. determine the types, incidence, course, and outcome of pulmonary and Cardiovascular disorders in these children and to elucidate the etiology and pathophysiology of these lung and heart abnormalities. The program is separated into three scopes: 1. Clinical and Laboratory - To recruit the required number of patients; coordinate clinical care with various studies outlined in this proposal and to provide core laboratory support for infectious and immunological components of this investigation. 2. Cardiology - To determine the natural history of cardiac disease in children with HIV infection and the incidence of both primary and secondary cardiac disease in children with perinatal HIV infection; identify early clinical marker of cardiac disease in infected children; determine laboratory markers and co-factors which precipitate clinical disease in infected patients. 3. Pulmonary - To study the natural history of pulmonary disorders in infants and children infected with HIV transmitted either in utero or during the perinatal period; collect information on the relationship between HIV infection and subsequent pulmonary growth, development and function; study the role of viruses; to identify tests that might aid in early diagnosis and treatment.